Device for producing infrared rays



June 26, 1951 E. E. w. KASSNER DEVICE FOR PRODUCING INFRARED RAYS 2Sheets-Sheet 1 Filed May 19, 1947 fiver/2'07 77757 6 14/ Kass/Yer Ixztorneg June 26, 1951 2 Sheets-Sheet 2 Filed May 19, 1947 r s e y M w aW 2 5 fl W W "M M w M M m w- F i- 9 m z Patented June 26, 1951 2,558,568DEVICE FOR PRODUCING INFRARED RAYS Ernst E. W. Kassner,Montana-Vermala-P/ Sierre,

Switzerland, assignor to Vibranic Ltd., Glaris, Switzerland, a societyof Switzerland Application May 19, 1947, Serial No. 749,050 InLuxembourg November 27, 1946 6 Claims. 1

In order to produce infra-red rays. it has been the usual practice up tothe present time to make use either of incandescent lamps or of gasdischarge lamps, these sources of infra-red rays having very differentemciencies. The word efficiency" designates the transformation ratio ofthe electric energy supplied by a source of current or a distributionsystem into radiating energy.

The chief object of my invention is to improve the efiiciency of devicesfor producing infra-red rays and more particularly the efiiciency insideone or several given frequency bands.

A preferred embodiment of my invention will be hereinafter describedwith reference to the accompanying drawings, given merely by way ofexample and in which:

Fig. 1 shows in diagrammatic section the lower portion of a lamp forproducing infra-red rays made according to an embodiment of myinvention.

Figs. 2 and 3 are views similar to Fig. 1 and illustrating anotherembodiment of my invention.

Fig. 4 is an axial sectional view of an accessory device to be used inconnection with the lamp of Figs. 1 to 3.

Figs. 5 and 6 are views similar to Fig. 4 and relating to modifications.

In the embodiment shown by Figs. 1 to 3, the lamp for producing.infra-red rays includes a glass bulb l, for instance of conventionalshape,

and the irmer face of which carries a reflectin layer 2 for directingthe rays towards the upper portion of the bulb. This upper portion ispreferably translucent so that the beam of rays issuing from the bulb ishomogeneous. According to the nature and shape of bulb I, this innerreflecting layer 2 may be replaced by a supplementary externalreflector.

Bulb l includesa conventional mount 3, either of the screw-threaded orof the bayonet type, through which the lamp can be directly inserted inthe electric distribution system. Mount 3 is provided in the usual waywith feed contacts 4 and 5. Base 6, made of insulating material, servesfor the passage of wires 4a. and 5a. which supply current to theelectrodes supported by said base 6.

The electrode system includes, on the one hand,

an incandescent electrode divided into several portions (filaments) and,on the other hand, several rod-shaped electrodes each of which is housedaxially in a portion of the incandescent electrode, all these electrodesbeing connected together as it will be hereinafter described. a

In the examplesshown by the drawings. I make use of two filaments 1a andlb respectively connected with their conductor supports 41) and 5b,themselves connected with feed wires la and 5a.

In Figs. 1 and 2, filaments la and lb are connected in series and inFig. 3 their connection is slightly different.

Each filament 1a or lb is wound to form a helix each spire of which maybe constituted either by a single winding or by a double winding. Inorder to support the filaments, I make use of glass cylinders 8 whichcarry supporting wires 9 to which the filaments are directly secured.Filaments 1a and 1b are parallel to each other and to the axis of bulb Iand they are located close to the focus of the reflector 2. They mightalso be disposed along the same line if it were desired to obtain alinolite lamp.

Electrodes Illa and lllb are constituted by small rods and each of themis fitted axially in the corresponding filament Ia or lb. These rodsllla and lllb are kept in position by having their free ends engaged inconductor and elastic supports lla and llb, for instance tight-woundhelical springs provided respectively at the top and bottom of each rod.

In the embodiment of Fig. 1, the ends of electrode l lla are connectedthrough its supports Ho and llb and wires l2a and I2!) to feed wire 50Electrode lllb is connected through its supports lla and l lb and wiresIn and I3!) to feed wire la. Stability of the whole of the electrodes isensured by an insulating glass piece l4 against which bear the free endsof feed wires 4a and 5a. The lower parts of these wires are separatedfrom each other by an insulating part l5 of the base portion 6 of thelamp.

In the embodiment of Fig. 2, the upper ends of electrodes Illa and lllbare connected through supports llb and wires IS with apoint ll of thewire-that connects filaments la; and lb with each other, wherebyelectrodes Illa and lob are fed with only one half of the networkvoltage. The lower ends of the electrodes are connected, throughsupports lla, with a piece l8 of an insulating material, itselfsupported by wires l9 carried by feed wires 40 and 5a.. The upperportion of the system of electrodes is held by a stirrup 20 constitutedby a wire carried by glass cylinders 8 and which supports an insulatingpiece 2| through which upper supports l lb and connection wires l6 areheld inposition.

In theembodiment of Fig. 3, filaments la and lb aremounted differently.Filament lb is connected, through its lower end, with feed wire 5b :and,through its upper end, with a wire 22 leading to the lower end offilament 1a. The upper end of this filament la isconnected with a ringfitted on the right hand side insulating cylinder I and connected withfeed wire a. Wire 22, which connects filaments 1a and lb together, alsofeeds current to electrodes Ia and llb through a wire l6a. Wire 22 alsoserves to support the upper part of the electrode system in position.The lower part of this system is held in position by insulating piece l8carried by wire elements IS.

The infra-red ray lamp of Fig. 1 works in the following manner.Supposing, for instance, that it is fed with 120 volts alternatingcurrent, filaments la and lb, which are made of suitable size, growincandescent since they are inserted in a closed circuit. As electrodesIlla and lb are connected with feed wires 4a and 4b through wires Ila-Rband |3cl3b, their alternating voltage is equal to that of the networkand as they are each laced inside an incandescent filament laor lb,theyare subjected to the radiations from said filaments. Once they havereached their temperature of equilibrium, they permit in turn, in thesame way as takes place for the filaments, of obtaining an infra-redradiation of the same kind. The infra-red rays that are producedtherefrom come both from filaments Ia and lb and from electrodes Illa,lllb in the form of rods. Therefore, the radiating surface is very wide.

In the case of a lamp such as shown by Fig. 2, filaments 1a and lb arefed with current in the same manner as in the case of Fig. 1, butelectrodes "la and Nb receive only one half of the network voltage sincethey are connected, through a wire IS, with a point half way betweensaid electrodes.

For the lamp of Fig. 3, electrodes Illa and I b are fed in the samemanner as in the case of Fig. 2 but, due to the particular arrangementof the feed circuit of filaments Ia and lb, the points thereof that areopposite one another respectively are always at the same potential sothat it is possible to feed the lamp with a higher alternating voltagewithout running any risk of a spark discharge taking place between thesefilaments even when they are located at a short distance from eachother. Therefore, this wiring arrangement is particularly advantageouswhen the lamp is fed with current of a voltage of 220 volts.

Electrodes Illa and "lb are made of a metal which may be the same asthat of filaments Ia and lb or different therefrom. They may consist ofeither solid or hollow rods. Preferably, and according to my invention,they are made of a calcined mixture of pure metals, such as tungsten,tantalum, molybdenum, and metallic salts, such as molybdenum sulphide ormagnesium, zirconium or cerium oxide. tures, the proportions of puremetal and metallic salt can be so chosen as to obtain a selectivedisplacement of the maximum of radiation toward the infra-red portion ofthe spectrum.

As shown by Figs. 4, and 6, I may, according to another feature of myinvention. surround each electrode I M or I0b with a perforated sleeve24 made of a material having a high melting point such as zirconiumoxide, magnesia, etc., this sleeve being disposed coaxially with respectto the electrode while being insulated therefrom by supports 24a. Theholes 25 provided in sleeve 24 may be either circular or of elongatedshape. They may be distributed in a regular manner either over the wholelength of the sleeve (Fig. 4)

With such calcined mixfor instance close to the ends (Fig. 5) or inthemiddle, etc. The area of these holes, with respect to the total areaof the sleeve, is such that a predetermined screen effect is obtainedfor a given potential. For instance, the size of the holes averages from0.1 to 0.5 mm. Due to the presence of the perforated sleeve, theintensity of the electronic current is limited and spark discharges areprevented. In order to obtain a good production of infra-red rays, theinternal pressure may advantageously be chosen equal to 500 mm. ofmercury, the bulb being filled with a mixture of argon and nitrogen.

If, according to my invention, discharge takes place in the lamp in anatmosphere of argon and nitrogen, and in the presence of a metallicvapour, more especially caesium vapour, especially when the partialpressure of caesium ranges from 0.01 to 0.001 of mercury, I obtain,simultaneously with the above mentioned production of rays, a resonanceradiation of the caesium vapour which corresponds chieflyto a spectralregion of 8,500 to 9,000 A".

The location of the discharge apertures 25 of insulated sleeves 24 maybe chosen, as shown by Fig. 6, in such manner that they correspond withthe potential nodes '26 of the ultra-short wavelengths to-be obtained.In order to determine these points, account must be taken of theexisting electrical conditions, such as the network voltage, of the gaspressure in which the discharge takes place, of the distance between thesleeve and the electrode, etc. Thus it becomes possible, by means of asingle system of electrodes and in the same lamp, of simultaneouslyproducing not only infra-red rays but also rays corresponding toultra-short waves, which involves important advantages for manyapplications, more especially when it is desired to act on the massitself of matter to be treated.

My invention therefore makes it possible to obtain, by means of a singlelamp, two complementary sets of electromagnetic waves, to wit onecorresponding to the infra-red band (A ranging from 0.8 to 3 a) butclose to light rays, and the other corresponding to the band ofultrashort waves (A ranging from 0.3 mm. to 50.0 cm. approximately)which adjoins the intra-red region, while obtaining two predeterminedinterrelated maximums, so as to correspond, concerning a great number oforgano-chemical substances, to the most important absorption rays ofthese substances.

In a general manner, while I have, in' the above description, disclosedwhat I deem to be practical and efficient embodiments of my invention,it should be well understood that I do not wish to be limited thereto asthere might be changes made in the arrangement, disposition and form ofthe parts without departing from the principle of the present inventionas comprehended within the scope of the accompanying claims.

What I claim is:

' 1. A device of the type described whichcomprises, in combination, abulb filled with a gaseous atmosphere, at least two radiating dischargeelectrodes in said bulb, constituted by parallel 1 metal rods, at leastone filament wound about each of said rods at a distance therefrom,electrical connections for causing current from the same source both tocirculate in closed circuit fashion through said filaments and to bringsaid discharge electrodes to a given potential, whereby infra-red raysare simultaneouslyradiated from said filaments and from said electrode,said electrode being within the field of the radiations of saidfilament, and a sleeve of a material having a high boiling pointsurrounding each of said electrodes, said sleeve, electrically insulatedfrom said electrode being provided with holes.

2. A device of the type described which comprises, in combination, abulb filled with a gaseous atmosphere, at least two radiating dischargeelectrodes in said bulb, constituted by parallel metal rods, at leastone filament wound about each of said rods at a distance therefrom,electrical connections for causing current from the same source both tocirculate in closed circuit fashion throughsaid filaments and to bringsaid discharge electrodesto a given potential, whereby infra-red raysare simultaneously radiated from said filaments and from said electrode,said electrode being within the field of the radiations of saidfilament, and a sleeve of a material having a high boiling pointsurrounding each of said electrodes, said sleeve, electrically insulatedfrom said electrode being provided with holes regularly distributed overthe whole surface thereof.

3. A device of the type described which comprises, in combination, abulb filled with a gaseous atmosphere, at least two radiating dischargeelectrodes in said bulb, constituted by parallel metal rods, at leastone filament wound about each of said rods at a distance therefrom,electrical connections for causing current from the same source both tocirculate in closed circuit fashion through said filaments and to bringsaid discharge electrodes to a given potential, whereby infra-red raysare simultaneously radiated from said filaments and from said electrode,said electrode being within the field of the radiations of saidfilament, and a sleeve of a material having a high boiling pointsurrounding each of said electrodes, said sleeve, electrically insulatedfrom said electrode being provided with holes grouped at certainportions of the surface thereof.

4. A device of the type described which comprises, in combination, abulb filled with a gaseous said filament, and a sleeve of a materialhaving a high boiling point surrounding each of said electrodes, saidsleeve, electrically insulated from said electrode being provided withholes grouped at the ends of the surface thereof.

5. A device of the type described which comprises, in combination, abulb filled with a gaseous atmosphere, at least two radiating dischargeelectrodes in said bulb, constituted by parallel metal rods, at leastone filament wound about each of said rods at a distance therefrom,electrical connections for causing current from the same source both tocirculate in closed circuit fashion through said filaments and to bringsaid discharge electrodes to a given potential, whereby infra-red raysare simultaneously radiated from said filaments and from said electrode,said electrode being within the field of the radiations of atmosphere,at least two radiating discharge electrodes in said bulb constituted byparallel metal rods, at least one filament wound about each of said rodsat a distance therefrom, two terminals adapted to be connected withcorresponding terminals of a source of current, two wires starting fromsaidfirst mentioned terminals, said filaments being connected in serieswith their lower ends connected with said wires respectively, and meansfor connecting both ends of one of said electrodes with one of saidwires and both ends of theother electrode with the other wire, wherebyinfra-red rays are simultaneously radiated from said filaments and fromsaid electrode, said electrode being within the field of the radiationsof said filament.

6. A device of the type described which comprises, in combination, abulb filled with a gaseous atmosphere, at least two radiating dischargeelectrodes in said bulb constituted by parallel metal rods, at least onefilament wound about each of said rods at a distance therefrom, twoterminals adapted to be connected with corresponding terminals of asource of current, two wires starting from said first mentionedterminals, said filaments being connected in series with their lowerends connected with said wires respectively, and means for connectingboth ends of one of said electrodes with the wire to which isconnectedthe lower end of the filament wound about the other electrode and meansfor connecting both ends of the other electrode with the other wire,whereby infra-red rays are simultaneously radiated from said filamentsand fromsaid electrode, said electrode being within the field oftheradiations of said filament.

ERNST E. W. KASSNE'R.

REFERENCES CITED The following references are of record in the NumberName Date 2,098,113 Spaeth Nov. 2, 1937 2,110,609 Rentschler et al Mar.8, 1938 2,116,689 Rompe May 10, 1938 2,203,482 Alexander June 4, 1940Smith Oct. 5, 1943

